Systematic Study on the Control of Lead in a New Building

摘要

A new building was identified as having high lead levels in its drinking water.Through a detailed sampling protocol, the sources of lead were identified as brass plumbing fittings and fixtures, and Pb:Sn solder. A study was performed in two isolated sections of the building plumbing system to determine if the lead levels could be reduced naturally with time by simply using the water. Significant reductions in lead levels were not achieved following 8 months of water usage. A second study was performed to evaluate the effectiveness of three chemical corrosion inhibitors: zinc orthophosphate, calcium orthophosphate, and sodium silicate, to reduce the lead levels. Three economic, simple, low maintenance chemical feed systems were designed and installed in three different isolated sections of the building's plumbing system. The chemicals were fed into the building sections for approximately 4 months. Results showed that all inhibitors effectively and rapidly reduced lead and copper levels.